Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 51
Filter
1.
Hum Vaccin Immunother ; 20(1): 2318814, 2024 Dec 31.
Article in English | MEDLINE | ID: mdl-38961639

ABSTRACT

The present study aimed at investigating whether the hydroxychloroquine (HCQ) treatment would impact the neutralizing antibody production, viremia levels and the kinetics of serum soluble mediators upon planned 17DD-Yellow Fever (YF) primovaccination (Bio-Manguinhos-FIOCRUZ) of primary Sjögren's syndrome (pSS). A total of 34 pSS patients and 23 healthy controls (HC) were enrolled. The pSS group was further categorized according to the use of HCQ (HCQ and Non-HCQ). The YF-plaque reduction neutralization test (PRNT ≥1:50), YF viremia (RNAnemia) and serum biomarkers analyses were performed at baseline and subsequent time-points (Day0/Day3-4/Day5-6/Day7/Day14-D28). The pSS group showed PRNT titers and seropositivity rates similar to those observed for HC (GeoMean = 238 vs 440, p = .11; 82% vs 96%, p = .13). However, the HCQ subgroup exhibited lower seroconversion rates as compared to HC (GeoMean = 161 vs 440, p = .04; 69% vs 96%, p = .02) and Non-HQC (GeoMean = 161 vs 337, p = .582; 69% vs 94%, p = .049). No differences in YF viremia were observed amongst subgroups. Serum biomarkers analyses demonstrated that HCQ subgroup exhibited increased levels of CCL2, CXL10, IL-6, IFN-γ, IL1-Ra, IL-9, IL-10, and IL-2 at baseline and displayed a consistent increase of several biomarkers along the kinetics timeline up to D14-28. These results indicated that HCQ subgroup exhibited a deficiency in assembling YF-specific immune response elicited by 17DD-YF primovaccination as compared to Non-HCQ subgroup. Our findings suggested that hydroxychloroquine is associated with a decrease in the humoral immune response after 17DD-YF primovaccination.


Subject(s)
Antibodies, Neutralizing , Antibodies, Viral , Hydroxychloroquine , Seroconversion , Sjogren's Syndrome , Yellow Fever , Humans , Hydroxychloroquine/therapeutic use , Sjogren's Syndrome/drug therapy , Sjogren's Syndrome/immunology , Female , Middle Aged , Male , Adult , Yellow Fever/immunology , Yellow Fever/prevention & control , Antibodies, Viral/blood , Antibodies, Neutralizing/blood , Yellow Fever Vaccine/immunology , Aged , Viremia/drug therapy , Viremia/immunology , Yellow fever virus/immunology , Cytokines/blood , Biomarkers/blood
2.
Vaccines (Basel) ; 12(6)2024 May 25.
Article in English | MEDLINE | ID: mdl-38932307

ABSTRACT

The yellow fever (YF) vaccine is one of the safest and most effective vaccines currently available. Still, its administration in people living with HIV (PLWH) is limited due to safety concerns and a lack of consensus regarding decreased immunogenicity and long-lasting protection for this population. The mechanisms associated with impaired YF vaccine immunogenicity in PLWH are not fully understood, but the general immune deregulation during HIV infection may play an important role. To assess if HIV infection impacts YF vaccine immunogenicity and if markers of immune deregulation could predict lower immunogenicity, we evaluated the association of YF neutralization antibody (NAb) titers with the pre-vaccination frequency of activated and exhausted T cells, levels of pro-inflammatory cytokines, and frequency of T cells, B cells, and monocyte subsets in PLWH and HIV-negative controls. We observed impaired YF vaccine immunogenicity in PLWH with lower titers of YF-NAbs 30 days after vaccination, mainly in individuals with CD4 count <350 cells/mm3. At the baseline, those individuals were characterized by having a higher frequency of activated and exhausted T cells and tissue-like memory B cells. Elevated levels of those markers were also observed in individuals with CD4 count between 500 and 350 cells/mm3. We observed a negative correlation between the pre-vaccination level of CD8+ T cell exhaustion and CD4+ T cell activation with YF-NAb titers at D365 and the pre-vaccination level of IP-10 with YF-NAb titers at D30 and D365. Our results emphasize the impact of immune activation, exhaustion, and inflammation in YF vaccine immunogenicity in PLWH.

3.
Sci Rep ; 14(1): 7709, 2024 04 02.
Article in English | MEDLINE | ID: mdl-38565882

ABSTRACT

The present study aimed at evaluating the YF-specific neutralizing antibody profile besides a multiparametric analysis of phenotypic/functional features of cell-mediated response elicited by the 1/5 fractional dose of 17DD-YF vaccine, administered as a single subcutaneous injection. The immunological parameters of each volunteer was monitored at two time points, referred as: before (Day 0) [Non-Vaccinated, NV(D0)] and after vaccination (Day 30-45) [Primary Vaccinees, PV(D30-45)]. Data demonstrated high levels of neutralizing antibodies for PV(D30-45) leading to a seropositivity rate of 93%. A broad increase of systemic soluble mediators with a mixed profile was also observed for PV(D30-45), with IFN-γ and TNF-α presenting the highest baseline fold changes. Integrative network mapping of soluble mediators showed increased correlation numbers in PV(D30-45) as compared to NV(D0) (532vs398). Moreover, PV(D30-45) exhibited increased levels of Terminal Effector (CD45RA+CCR7-) CD4+ and CD8+ T-cells and Non-Classical memory B-cells (IgD+CD27+). Dimensionality reduction of Mass Cytometry data further support these findings. A polyfunctional cytokine profile (TNF-α/IFN-γ/IL-10/IL-17/IL-2) of T and B-cells was observed upon in vitro antigen recall. Mapping and kinetics timeline of soluble mediator signatures for PV(D30-45) further confirmed the polyfunctional profile upon long-term in vitro culture, mediated by increased levels of IFN-γ and TNF-α along with decreased production of IL-10. These findings suggest novel insights of correlates of protection elicited by the 1/5 fractional dose of 17DD-YF vaccine.


Subject(s)
Yellow Fever Vaccine , Yellow Fever , Humans , Adult , Antibodies, Neutralizing , Interleukin-10 , Antibodies, Viral , Tumor Necrosis Factor-alpha , CD8-Positive T-Lymphocytes , Vaccination
4.
NPJ Vaccines ; 9(1): 54, 2024 Mar 08.
Article in English | MEDLINE | ID: mdl-38459059

ABSTRACT

The re-emergence of yellow fever (YF) urged new mass vaccination campaigns and, in 2017, the World Health Organization approved the use of the fractional dose (FD) of the YF vaccine due to stock shortage. In an observational cross-sectional investigation, we have assessed viremia, antibodies, soluble mediators and effector and memory T and B-cells induced by primary vaccination of volunteers with FD and standard dose (SD). Similar viremia and levels of antibodies and soluble markers were induced early after immunization. However, a faster decrease in the latter was observed after SD. The FD led to a sustained expansion of helper T-cells and an increased expression of activation markers on T-cells early after vaccination. Although with different kinetics, expansion of plasma cells was induced upon SD and FD immunization. Integrative analysis reveals that FD induces a more complex network involving follicular helper T cells and B-cells than SD. Our findings substantiate that FD can replace SD inducing robust correlates of protective immune response against YF.

5.
Vaccine ; 42(11): 2729-2732, 2024 Apr 19.
Article in English | MEDLINE | ID: mdl-38514353

ABSTRACT

Studies on yellow fever vaccine (YF) in chronic kidney disease (CKD) patients are scarce. This cross-sectional study aimed to evaluate YF neutralizing antibody seroprevalence and titers in previously vaccinated adults with CKD, on dialysis (D-CKD) or not (ND-CKD), compared to healthy persons. The micro Plaque Reduction Neutralization-Horseradish Peroxidase (µPRN-HP) test was used. Antibody titers were expressed as the reciprocal of the highest dilution that neutralized the challenge virus by 50 % (µPRN50). Seropositivity cut-off was set at ≥ 1:100. We included 153 participants: 46 ND-CKD, 50 D-CKD and 57 healthy adults. Median ages were 58.3, 55 and 52.2 years, respectively. Median time since YF vaccination was 22.3, 18.5 and 48.3 months respectively. There were no statistically significant differences in YF seroprevalence and neutralizing antibodies titers among groups: 100 % of ND-CKD; 96 % of D-CKD and 100 % of healthy participants were seropositive. Geometric mean titers (GMT) were 818.5, 683.0 and 665.5, respectively (p = 0.289).


Subject(s)
Renal Insufficiency, Chronic , Yellow Fever Vaccine , Yellow Fever , Adult , Humans , Yellow Fever/prevention & control , Antibodies, Neutralizing , Cross-Sectional Studies , Seroepidemiologic Studies , Antibodies, Viral , Yellow fever virus , Vaccination , Renal Insufficiency, Chronic/complications , Renal Insufficiency, Chronic/therapy
6.
Diseases ; 12(1)2024 Jan 18.
Article in English | MEDLINE | ID: mdl-38248380

ABSTRACT

Massive vaccination positively impacted the SARS-CoV-2 pandemic, being a strategy to increase the titers of neutralizing antibodies (NAbs) in the population. Assessing NAb levels and understanding the kinetics of NAb responses is critical for evaluating immune protection. In this study, we optimized and validated a PRNT50 assay to assess 50% virus neutralization and evaluated its accuracy to measure NAbs to the original strain or variant of SARS-CoV-2. The optimal settings were selected, such as the cell (2 × 105 cells/well) and CMC (1.5%) concentrations and the viral input (~60 PFU/well) for PRNT-SARS-CoV-2 with cut-off point = 1.64 log5 based on the ROC curve (AUC = 0.999). The validated PRNT-SARS-CoV-2 assay presented high accuracy with an intraassay precision of 100% for testing samples with different NAb levels (low, medium, and high titers). The method displays high selectivity without cross-reactivity with dengue (DENV), measles (MV), zika (ZIKV), and yellow fever (YFV) viruses. In addition, the standardized PRNT-SARS-CoV-2 assay presented robustness when submitted to controlled variations. The validated PRNT assay was employed to test over 1000 specimens from subjects with positive or negative diagnoses for SARS-CoV-2 infection. Patients with severe COVID-19 exhibited higher levels of NAbs than those presenting mild symptoms for both the Wuhan strain and Omicron. In conclusion, this study provides a detailed description of an optimized and validated PRNT50 assay to monitor immune protection and to subsidize surveillance policies applied to epidemiologic studies of COVID-19.

7.
Pharmaceuticals (Basel) ; 16(10)2023 Sep 25.
Article in English | MEDLINE | ID: mdl-37895823

ABSTRACT

Despite the rapid mass vaccination against COVID-19, the emergence of new SARS-CoV-2 variants of concern, such as omicron, is still a great distress, and new therapeutic options are needed. Bovine lactoferrin (bLf), a multifunctional iron-binding glycoprotein available in unsaturated (apo-bLf) and saturated (holo-bLf) forms, has been shown to exert broad-spectrum antiviral activity against many viruses. In this study, we evaluated the efficacy of both forms of bLf at 1 mg/mL against infection of Vero cells by SARS-CoV-2. As assessed with antiviral assays, an equivalent significant reduction in virus infection by about 70% was observed when either form of bLf was present throughout the infection procedure with the SARS-CoV-2 ancestral or omicron strain. This inhibitory effect seemed to be concentrated during the early steps of virus infection, since a significant reduction in its efficiency by about 60% was observed when apo- or holo-bLf were incubated with the cells before or during virus addition, with no significant difference between the antiviral effects of the distinct iron-saturation states of the protein. However, an ultrastructural analysis of bLf treatment during the early steps of virus infection revealed that holo-bLf was somewhat more effective than apo-bLf in inhibiting virus entry. Together, these data suggest that bLf mainly acts in the early events of SARS-CoV-2 infection and is effective against the ancestral virus as well as its omicron variant. Considering that there are no effective treatments to COVID-19 with tolerable toxicity yet, bLf shows up as a promising candidate.

8.
Vaccine ; 41(44): 6514-6528, 2023 Oct 20.
Article in English | MEDLINE | ID: mdl-37661534

ABSTRACT

New variants of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) have emerged, imposing the need for periodic booster doses. However, whether booster doses should be applied to the entire population or groups, and the booster doses interval, remains unclear. In this study, we evaluated humoral reactivity kinetics from before the first dose to 180 days after the third booster dose in different schedules in a well-controlled health worker cohort. Among the 2,506 employees, the first 500 vaccinated health workers were invited to participate. The third booster dose was administered 8 months after the first dose. Among the invited participants, 470 were included in the study; 258 received inactivated vaccine CoronaVac (VAC group) and 212 received viral vector vaccine ChAdOx1 (AZV group). The groups were homogeneous in terms of age and sex. 347 participants were followed up after the booster dose with AZV or BNT162b2 (Pfizer, BNT group): 63 with VAC/AZV, 117 with VAC/BNT, 72 with the AZV/AZV and 95 with AZV/BNT schedules. Blood samples were collected immediately before, 28 days after each dose and 180 days after the primary vaccination and booster dose. Anti-SARS-CoV-2 antibodies were measured by chemiluminescence and plaque reduction neutralization test (PRNT). Plasma immune mediators were quantified using a multiplex immunoassay. Geometric mean of antibodies increased 28 days after the second dose with 100 % seroconversion rate in both groups and decreased 180 days after the first dose. In the baseline-seropositive VAC group, the levels of plasma immune mediators increased after the second dose. Booster dose was applied at 4-6 months after the primary vaccination. Heterologous booster in VAC or AZV primary vaccinees were effective maintaining the titers of anti-SARS-CoV-2 antibodies even after 6 months of follow-up. The heterologous schedule induced higher and stable antibody reactivity, even after 180 days, protecting to ancestral (Wuhan), Delta, and Omicron variants.

9.
AIDS ; 37(15): 2319-2329, 2023 12 01.
Article in English | MEDLINE | ID: mdl-37650759

ABSTRACT

OBJECTIVE: To evaluate immunogenicity and reactogenicity of yellow fever (YF) vaccine in people with HIV (PWH) compared to HIV-uninfected controls. DESIGN: In this longitudinal interventional trial (NCT03132311), PWH with CD4 + cell count ≥200 cells/µl and controls, aged 18-59, without a previous history of YF vaccination received a single standard dose of YF vaccine (17DD) and were followed at Days 5, 30 and Year 1. METHODS: YF-neutralization titers were measured at Days 0, 30 and Year 1 and geometric mean titers (GMT) were calculated. Adverse events (AE) and YF virus detection were measured at Days 5 and 30. Linear regression evaluated factors associated with YF-neutralization titers. RESULTS: Two hundred and eighteen PWH and 82 controls were included. At baseline, all PWH were using antiretroviral therapy; 92.6% had undetectable HIV viral load (VL) and median CD4 + cell count was 630 cells/µl [interquartile range (IQR) 463-888]. YF vaccine was safe and there were no serious AEs. At Day 30, seroconversion was observed in 98.6% of PWH [95% confidence interval (CI): 95.6-99.6] and in 100% of controls (95% CI: 93.9-100); at Year 1, 94.0% of PWH (95% CI: 89.6-96.7) and 98.4% of controls (95% CI 90.3-99.9) were seropositive. PWH had lower GMTs than controls at Day 30 and Year 1. Baseline VL >1000 copies/ml, low CD4 + cell count and low CD4 + /CD8 + ratio were associated with lower YF-neutralization titers. CONCLUSIONS: YF vaccine is safe in PWH with CD4 + cell count ≥200 cells/µl. YF vaccine immunogenicity is impaired in PWH, particularly among those with high VL, low CD4 + cell count and low CD4 + /CD8 + ratio at vaccination and YF-neutralization titers decays over time.


Subject(s)
HIV Infections , Yellow Fever Vaccine , Yellow Fever , Humans , Yellow Fever/prevention & control , Antibodies, Neutralizing , HIV Infections/complications , Vaccination/adverse effects , Antibodies, Viral
10.
Materials (Basel) ; 16(14)2023 Jul 12.
Article in English | MEDLINE | ID: mdl-37512248

ABSTRACT

This paper presents an experimental study about the use of innovative bio-based pultruded carbon-fiber-reinforced polymer (CFRP) laminates for structural strengthening. The bio-based laminates were produced in the framework of an applied research project (BioLam) using a resin system with 50% (wt.%) bio-based content, obtained from renewable resources. In the first part of the study, their tensile and interlaminar shear properties were characterized and compared with those of conventional oil-based CFRP laminates. In the second part of the study, the bond behavior to concrete of both types of CFRP laminates applied according to the externally bonded reinforcement (EBR) technique was assessed by means of single-lap shear tests performed on CFRP-strengthened concrete blocks; the experimental results obtained from these tests were then used in a numerical procedure to calibrate local bond vs. slip laws for both types of laminates. The final part of this study comprised four-point bending tests on full-scale EBR-CFRP-strengthened reinforced concrete (RC) beams to assess the structural efficacy of the bio-based laminates; these were benchmarked with tests performed on similar RC beams strengthened with conventional CFRP laminates. The results obtained in this study show that the (i) material properties, (ii) the bond behavior to concrete, and (iii) the structural efficacy of the developed bio-based CFRP laminates are comparable to those of their conventional counterparts, confirming their potential to be used in the strengthening of RC structures.

11.
Front Med (Lausanne) ; 10: 1192070, 2023.
Article in English | MEDLINE | ID: mdl-37324152

ABSTRACT

Glioblastoma is the most frequent and aggressive primary brain cancer. In preclinical studies, Zika virus, a flavivirus that triggers the death of glioblastoma stem-like cells. However, the flavivirus oncolytic activity has not been demonstrated in human patients. Here we report a glioblastoma patient who received the standard of care therapy, including surgical resection, radiotherapy and temozolomide. However, shortly after the tumor mass resection, the patient was clinically diagnosed with a typical arbovirus-like infection, during a Zika virus outbreak in Brazil. Following the infection resolution, the glioblastoma regressed, and no recurrence was observed. This clinical response continues 6 years after the glioblastoma initial diagnosis.

12.
J Toxicol Environ Health A ; 86(4): 87-102, 2023 02 16.
Article in English | MEDLINE | ID: mdl-36756732

ABSTRACT

The aim of this study was to determine the oxidative/antioxidative effects, modulatory and selective potential of α-tocopherol (vitamin E) on antineoplastic drug-induced toxicogenetic damage. The toxicity, cytotoxicity and genotoxicity induced by antineoplastic agents cyclophosphamide (CPA) and doxorubicin (DOX) was examined utilizing as models Saccharomyces cerevisiae, Allium cepa, Artemia salina and human peripheral blood mononuclear cells (PBMCs) in the presence of α-tocopherol. For these tests, concentrations of α- tocopherol 100 IU/ml (67mg/ml), CPA 20 µg/ml, DOX 2 µg/ml were used. The selectivity of α-tocopherol was assessed by the MTT test using human mammary gland non-tumor (MCF10A) and tumor (MCF-7) cell lines. Data showed cytoplasmic and mitochondrial oxidative damage induced by CPA or DOX was significantly diminished by α-tocopherol in S. cerevisiae. In addition, the toxic effects on A. salina and cytotoxic and mutagenic effects on A. cepa were significantly reduced by α-tocopherol. In PBMCs, α-tocopherol alone did not markedly affect these cells, and when treated in conjunction with CPA or DOX, α-tocopherol reduced the toxicogenetic effects noted after antineoplastic drug administration as evidenced by decreased chromosomal alterations and lowered cell death rate. In human mammary gland non-tumor and tumor cell lines, α-tocopherol produced selective cytotoxicity with 2-fold higher effect in tumor cells. Evidence indicates that vitamin E (1) produced anti-cytotoxic and anti-mutagenic effects against CPA and DOX (2) increased higher selectivity toward tumor cells, and (3) presented chemoprotective activity in PBMCs.


Subject(s)
Antineoplastic Agents , alpha-Tocopherol , Humans , alpha-Tocopherol/pharmacology , Saccharomyces cerevisiae , Leukocytes, Mononuclear , Antineoplastic Agents/toxicity , Antineoplastic Agents/therapeutic use , Doxorubicin/toxicity , Cyclophosphamide/toxicity , Vitamin E
13.
Front Immunol ; 13: 966416, 2022.
Article in English | MEDLINE | ID: mdl-36105814

ABSTRACT

Fractional dose is an important strategy to increase access to vaccines. This study evaluated the effectiveness, safety, and immunogenicity of half dose of ChAdOx1 nCoV-19 vaccine. A non-inferiority non-randomized controlled trial compared a half dose of ChAdOx1 nCoV-19 with the full dose, with an interval of 8 to 10 weeks, in individuals aged 18-49 years. The primary endpoints were the incidence rate of new cases/1,000 person-year at 90 days after 14 days of the second dose, confirmed by RT-PCR and new cases registered at SUS National Health Surveillance Database (e-SUS VS). The anti-SARS-CoV-2 spike (S) protein receptor binding domain (RBD) by chemiluminescence and the neutralizing antibodies by plaque reduction neutralization test (PRNT) were titrated. The soluble biomarkers were quantified with a multiplex immunoassay. Follow-up was 90 days after 14 days of the second dose. A total of 29,598 individuals were vaccinated. After exclusion, 16,570 individuals who received half a dose and 6,402 who received full doses were analyzed. The incidence of new cases confirmed by RT-PCR of half dose was non-inferior to full dose (23.7 vs. 25.7 cases per 1,000 persons-year [coefficient group -0.09 CI95%(-0.49 to 0.31)], even after adjusting for age and sex. There were no deaths or hospitalization after immunization of either group. Immunogenicity was evaluated in a subsample (N=558) compared to 154 healthcare workers who received a full dose. The seroconversion rate in seronegative individuals at baseline half dose was 99.8%, similar to that of the full dose (100%). Geometric mean concentration (95% CI; BAU/mL) were half dose = 188 (163-217) and full dose = 529 (423-663) (p < 0.001). In seropositive subjects at baseline (pre-immune individuals), the first dose induced very high and similar IgG-S in half dose 1,359 (1,245-1,483) and full dose 1,354 (1,048-1,749) BAU/mL. A half dose induced a high increase in plasma chemokines, pro-inflammatory/regulatory cytokines, and growth factors. The frequency of adverse events was similar. No serious adverse events or deaths were reported. A half dose of ChAdOx1 nCoV-19 is as effective, safe, and immunogenic as the full dose. The immune response in pre-immune (seropositive in the baseline) individuals indicates that the half dose may be a booster dose schedule.


Subject(s)
COVID-19 Vaccines , COVID-19 , ChAdOx1 nCoV-19 , Antibodies, Neutralizing , Antibodies, Viral , COVID-19/prevention & control , COVID-19 Vaccines/adverse effects , Humans
14.
Viruses ; 14(9)2022 08 30.
Article in English | MEDLINE | ID: mdl-36146723

ABSTRACT

Infections caused by SARS-CoV-2 induce a severe acute respiratory syndrome called COVID-19 and have led to more than six million deaths worldwide. Vaccination is the most effective preventative measure, and cellular and humoral immunity is crucial to developing individual protection. Here, we aim to investigate hybrid immunity against SARS-CoV-2 triggered by the ChAadOx1 nCoV-19 vaccine in a Brazilian cohort. We investigated the immune response from ChAadOx1 nCoV-19 vaccination in naïve (noCOVID-19) and previously infected individuals (COVID-19) by analyzing levels of D-dimers, total IgG, neutralizing antibodies (Nabs), IFN-γ (interferon-γ) secretion, and immunophenotyping of memory lymphocytes. No significant differences in D-dimer levels were observed 7 or 15 days after vaccination (DAV). All vaccinated individuals presented higher levels of total IgG or Nabs with a positive correlation (R = 0.88). Individuals in the COVID-19 group showed higher levels of antibody and memory B cells, with a faster antibody response starting at 7 DAV compared to noCOVID-19 at 15 DAV. Further, ChAadOx1 nCoV-19 vaccination led to enhanced IFN-γ production (15 DAV) and an increase in activated T CD4+ naïve cells in noCOVID-19 individuals in contrast with COVID-19 individuals. Hence, our data support that hybrid immunity triggered by ChAadOx1 nCoV-19 vaccination is associated with enhanced humoral response, together with a balanced cellular response.


Subject(s)
COVID-19 , Viral Vaccines , Antibodies, Neutralizing , Antibodies, Viral , COVID-19/prevention & control , COVID-19 Vaccines , ChAdOx1 nCoV-19 , Humans , Immunity, Cellular , Immunity, Humoral , Immunoglobulin G , Interferon-gamma , SARS-CoV-2 , Vaccination
15.
Viruses ; 14(7)2022 06 30.
Article in English | MEDLINE | ID: mdl-35891431

ABSTRACT

The occurrence of dengue disease has increased radically in recent decades. Previously, we constructed the pE1D2 and pcTPANS1 DNA vaccines encoding the DENV2 envelope (E) and non-structural 1 (NS1) proteins, respectively. To decrease the number of plasmids in a tetravalent candidate vaccine, we constructed a bicistronic plasmid, pNS1/E/D2, encoding these two proteins simultaneously. We evaluated the protective immunity induced in mice vaccinated with the pNS1/E/D2 candidate and compared to the responses elicited by immunization with the former vaccines isolated or in combination. We transfected BHK-21 cells with the different plasmids and detected recombinant proteins by immunofluorescence and mass spectrometry assays to confirm antigen expression. BALB/c mice were inoculated with the DNA vaccines followed by a lethal DENV2 challenge. ELISA, PRNT50, and IFN-gamma ELISPOT assays were performed for the investigation of the humoral and cellular responses. We observed the concomitant expression of NS1 and E proteins in pNS1/E/D2-transfected cells. All E-based vaccines induced anti-E and neutralizing antibodies. However, anti-NS1 antibodies were only observed after immunization with the pcTPANS1 administered alone or combined with pE1D2. In contrast, splenocytes from pNS1/E/D2- or pcTPANS1 + pE1D2-vaccinated animals responded to NS1- and E-derived synthetic peptides. All the DNA vaccines conferred protection against DENV2.


Subject(s)
Dengue Vaccines , Dengue Virus , Dengue , Vaccines, DNA , Animals , Antibodies, Viral , Dengue/prevention & control , Dengue Vaccines/genetics , Dengue Virus/genetics , Immunity , Mice , Mice, Inbred BALB C , Vaccines, DNA/genetics , Viral Nonstructural Proteins/genetics
16.
Vaccine X ; 10: 100131, 2022 Apr.
Article in English | MEDLINE | ID: mdl-34977552

ABSTRACT

Yellow fever vaccine (YFV) is a live attenuated vaccine usually contraindicated for juvenile autoimmune rheumatic disease (JARD) patients. During the recent epidemic in Sao Paulo-Brazil, YFV was indicated for patients under low immunosuppression. Thirty JARD patients with inactive diseases undergoing low immunosuppression and 30 healthy controls (HC) were vaccinated with a fractional dose 17DD YFV (∼5495 IU) and evaluated 30 days later. JARD patients and controls had comparable median age (12.4 vs. 12 years, p = 0.250). Disease parameters remained stable 30 days after 17DD YFV (p > 0.05) and only mild adverse events were reported in both groups (p > 0.05). JARD and HC had similar seroprotection [93% vs. 100%;p = 0.49], seroconversion rates [96% vs. 100%;p = 0.489], and GMT [1249 vs.1293;p = 0.821]. Both groups had similar white-blood-cells kinetics with transient decreases in lymphocytes at D5 and neutrophils at D10, followed by full recovery at D30 (P < 0.05). In conclusion, 17DD YFV was safe and immunogenic in JARD. This study may contribute to recommendations for patients living/travelling to endemic areas.

17.
Vaccine ; 40(5): 798-810, 2022 01 31.
Article in English | MEDLINE | ID: mdl-34969545

ABSTRACT

The present investigation comprised two independent observational arms to evaluate the influence of pre-existing flavivirus humoral immunity and the age-impact on 17DD-YF vaccination immunity. Flavivirus (YFV; DENV; ZIKV) serology and YF-specific cellular immunity was evaluated in 288 children/9Mths-4Yrs and 288 adults/18-49Yrs residents of areas without YFV circulation. Data demonstrated that flavivirus seropositivity at baseline was higher in Adults as compared to Children (26%;87%;67% vs 6%;13%;15%, respectively). The heterologous flavivirus seropositivity (DENV; ZIKV) did not impact the YF-specific cellular immune response at baseline. However, higher levels of NCD4, EMCD8, IFN-MCD8, NCD19 and nCMCD19 were observed in subjects with pre-existing YFV seropositivity. Primary vaccination of YFV-seronegative volunteers led to higher levels of YF-neutralizing antibodies in Adults as compared to Younger Children (9Mths-2Yrs). Although similar seropositivity rates observed amongst Children and Adults at D30-45, lower rates were observed in Younger Children (9Mths-2Yrs) at D365 (94%;95%;100% vs 87%;96%;99%, respectively). A progressive decline in antibody levels were reported at D365, being more expressive in Children as compared to Adults. All age-subgroups exhibited at D30-45 increased levels of eEfCD4, EMCD4, IFN-MCD8 and nCMCD19 together with a decrease of eEfCD8 and CMCD8. While an increase of EMCD8 were observed in all subgroups at D30-45, a declined duration at D365 was reported only in Younger Children (9Mths-2Yrs). Biomarker signatures further support that only Younger Children (9Mths-2Yrs) presented a progressive decline of EMCD8 at D365. Together, these findings demonstrated that regardless the similarities observed in YF-neutralizing antibodies, the age impacts the duration of cellular immune response to primary 17DD-YF vaccination.


Subject(s)
Yellow Fever Vaccine , Yellow Fever , Zika Virus Infection , Zika Virus , Adult , Antibodies, Neutralizing , Antibodies, Viral , Child , Humans , Immunity, Cellular , Vaccination , Yellow Fever/prevention & control , Yellow fever virus
18.
Infect Control Hosp Epidemiol ; 43(2): 174-180, 2022 02.
Article in English | MEDLINE | ID: mdl-34128460

ABSTRACT

OBJECTIVE: Assess the accumulation of protein and biofilm on the inner surfaces of new flexible gastroscope (FG) channels after 30 and 60 days of patient use and full reprocessing. DESIGN: Clinical use study of biofilm accumulation in FG channels. SETTING: Endoscopy service of a public hospital. METHODS: First, we tested an FG in clinical use before the implementation of a revised reprocessing protocol (phase 1 baseline; n = 1). After replacement of the channels by new ones and the implementation of the protocol, 3 FGs were tested after 30 days of clinical use (phase 2; n = 3) and 3 FGs were tested after 60 days of clinical use (phase 3; n = 3), and the same FGs were tested in phase 2 and 3. Their biopsy, air, water, and air/water junction channels were removed and subjected to protein testing (n = 21), bacteriological culture (n = 21), and scanning electron microscopy (SEM) (n = 28). Air-water junction channels fragments were subjected to SEM only. RESULTS: For the FGs, the average number of uses and reprocessing cycles was 60 times. Extensive biofilm was detected in air, water, and air-water junction channels (n = 18 of 28). All channels (28 of 28) showed residual matter, and structural damage was identified in most of them (20 of 28). Residual protein was detected in the air and water channels of all FG evaluated (phases 1-3), except for 1 air channel from phase 2. Bacteria were recovered from 8 of 21 channels, most air or water channels. CONCLUSIONS: The short time before damage and biofilm accumulation in the channels was evident and suggests that improving the endoscope design is necessary. Better reprocessing methods and channel maintenance are needed.


Subject(s)
Equipment Contamination , Gastroscopes , Biofilms , Disinfection/methods , Endoscopes/microbiology , Humans
19.
PLoS Negl Trop Dis ; 15(11): e0010002, 2021 11.
Article in English | MEDLINE | ID: mdl-34843469

ABSTRACT

BACKGROUND: Brazil faced a yellow fever(YF) outbreak in 2016-2018 and vaccination was considered for autoimmune rheumatic disease patients(ARD) with low immunosuppression due to YF high mortality. OBJECTIVE: This study aimed to evaluate, prospectively for the first time, the short-term immunogenicity of the fractional YF vaccine(YFV) immunization in ARD patients with low immunossupression. METHODS AND RESULTS: A total of 318 participants(159 ARD and 159 age- and sex-matched healthy controls) were vaccinated with the fractional-dose(one fifth) of 17DD-YFV. All subjects were evaluated at entry(D0), D5, D10, and D30 post-vaccination for clinical/laboratory and disease activity parameters for ARD patients. Post-vaccination seroconversion rate(83.7%vs.96.6%, p = 0.0006) and geometric mean titers(GMT) of neutralizing antibodies[1143.7 (95%CI 1012.3-1292.2) vs.731 (95%CI 593.6-900.2), p<0.001] were significantly lower in ARD compared to controls. A lower positivity rate of viremia was also identified for ARD patients compared to controls at D5 (53%vs.70%, p = 0.005) and the levels persisted in D10 for patients and reduced for controls(51%vs.19%, p = 0.0001). The viremia was the only variable associated with seroconvertion. No serious adverse events were reported. ARD disease activity parameters remained stable at D30(p>0.05). CONCLUSION: Fractional-dose 17DD-YF vaccine in ARD patients resulted in a high rate of seroconversion rate(>80%) but lower than controls, with a longer but less intense viremia. This vaccine was immunogenic, safe and did not induce flares in ARD under low immunosuppression and may be indicated in YF outbreak situations and for patients who live or travel to endemic areas. TRIAL REGISTRATION: This clinical trial was registered with Clinicaltrials.gov (#NCT03430388).


Subject(s)
Rheumatic Diseases/immunology , Yellow Fever Vaccine/immunology , Yellow Fever/prevention & control , Adult , Antibodies, Neutralizing/immunology , Antibodies, Viral/immunology , Brazil , Female , Humans , Immunosuppression Therapy , Male , Middle Aged , Prospective Studies , Seroconversion , Yellow Fever/immunology , Yellow Fever Vaccine/administration & dosage , Yellow Fever Vaccine/adverse effects , Young Adult
20.
Rev. psicol. polit ; 21(50): 154-167, jan.-abr. 2021. ilus
Article in Portuguese | LILACS-Express | LILACS, Index Psychology - journals | ID: biblio-1289949

ABSTRACT

RESUMO "Estourar a bolha social" é uma expressão utilizada por estudantes de psicologia para indicar sentimentos de perplexidade e indignação frente à violação de direitos sociais de usuários atendidos em três diferentes espaços de formação acadêmica. Esta expressão explicita o véu de proteção que impede o sujeito de enxergar para além de seu lugar de classe social e conforto socioeconômico. A proposta deste artigo é apresentar experiências que expõem os estudantes ao sofrimento disparado em situações de desigualdades econômicas: a supervisão que problematiza a responsabilidade ética; a intervenção realizada com moradores que foram removidos de suas casas em violentas ações de reintegração de posse; a articulação entre o agir profissional e a produção de narrativas de histórias de vida. Nestas propostas descobre-se o valor da escuta na formação tensionando discursos de saber-poder, por vezes aprisionantes e, por vezes, capazes de dar visibilidade a histórias de vida frequentemente esquecidas.


ABSTRACT "Burst the social bubble" is an expression used by psychology students to indicate feelings of perplexity and indignation regarding the violation of social rights of users in three different spaces of academic formation. This expression makes explicit the veil of protection that prevents the subject from seeing beyond their place of social class and socioeconomic comfort. The purpose of this article is to present experiences that expose students to sociopolitical suffering triggered in situations of economic inequality: supervision that problematizes ethical responsibility; the intervention carried out with residents who were removed from their homes in violent repossession actions; the articulation between professional acting and the production of life story narratives. In these proposals we discover the value of listening in training by tensioning discourses of knowledge, sometimes imprisoning and sometimes capable of giving visibility to life stories that are often forgotten.


RESUMEN "Estallar la burbuja social" es una expresión utilizada por estudiantes de psicología para indicar sentimientos de perplejidad e indignación hacia a la violación de derechos sociales de usuarios atendidos en espacios de formación académica. Esta expresión evidencia el velo que impide que el sujeto vea más allá de su clase social y confort socioeconómico. Este artículo pretende presentar experiencias que expongan a los estudiantes el sufrimiento sociopolítico desencadenado en situaciones de desigualdad económica: supervisión que problematiza la responsabilidad ética; la intervención llevada a cabo con residentes que fueron retirados de sus hogares en acciones violentas de recuperación; la articulación entre actuación profesional y producción de narraciones de historias de vida. En estas propuestas descubrimos el valor de escuchar en la formación al tensar el discurso de saber-poder, a veces opresor y otras siendo capaces de dar visibilidad a las historias de vida que a menudo se olvidan.

SELECTION OF CITATIONS
SEARCH DETAIL
...